This invention relates to a voltage driver for a memory.
Voltage xe2x80x9csnap-backxe2x80x9d is a phenomenon that occurs when the drain voltage of an N-channel transistor is high and the gate voltage of the transistor switches from low voltage to a higher voltage. During snap-back, ionization current from the N-channel transistor flows into the transistor substrate. This causes the substrate to bias upwards, which forward biases the drain-source junction causing more current to flow through the transistor into the substrate. This positive feedback effect can destroy the transistor.
One method of eliminating snap-back includes increasing the N-channel length of the transistor. This method affects the transistors speed of operation, requiring an increase in its channel width to maintain a constant speed. Increasing the channel width, however, increases the size of the transistor. This is problematic when chip space is limited.